In palaeodietary studies it is assumed that no discrimination occurs during uptake by plants of calcium and strontium from the soil. Here, a compilation of distribution ratios is presented from which it is apparent that differences in strontium/calcium ratios within and between plants do exist. These differences affect strontium intake by humans and animals and thus should be taken into consideration when interpreting prehistoric human bone strontium levels in a dietary sense, and when selecting a herbivorous baseline species. In agricultural societies, human strontium intake may be diversified by differences in strontium/calcium ratios in various grain species and varieties. -- AATA